Although giant cell arteritis (GCA), clinically designated as temporal arteritis, is recognized as a systemic disease, the breast may be the primary organ in which it is manifested. GCA of the breast is a rare disease that mainly occurs in postmenoposal elderly women. It manifests as nodules or pain in the breast, with or without tenderness, and is associated with significant constitutional symptoms that resemble those of polymyalgia rheumatica (PMR). These symptoms can be treated with or without prednisone therapy and can improve without the development of organ dysfunction. The clinical manifestations can often be recognized only by retrospective analysis after excisional biopsy. GCA of the breast occasionally mimics carcinoma, and its initial manifestations may be similar to those of other forms of vasculitis involving the breast, such as polyarteritis nodosa and Wegener granulomatosis. Biopsy is indispensable for establishing a definitive diagnosis. Thus far, the findings of imaging procedures, such as mammography and ultrasonography, for patients with mammary GCA have not been reported in detail, and no distinctive findings associated with this condition have been identified. Considering this and the fact that spontaneous remission may occur in some cases, mammary GCA probably often goes undiagnosed or may be misdiagnosed as an ordinary mammary disease. GCA of the breast should be considered as a potential diagnosis in the case of elderly women presenting with PMR-like symptoms and tenderness, lumps, or pain in the breast. We report a case of GCA affecting the breast and review previous reports on this condition in an attempt to summarize the features that distinguish this disease from other vascular diseases of the breast.